JPH09223511A - Power supply - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To prevent the danger due to exhaust gas at the time of power source operation, to securely seal the fuel cell body when the power source is not used, and to reduce the pressure due to the residual gas consumption in the fuel cell body after the operation is stopped. Prevent decline. SOLUTION: A combustion section 21 for introducing exhaust gas from a fuel gas outlet 4 and an air outlet 5 of a fuel cell main body 6, an exhaust gas outlet 27 provided in the combustion section 21, and an air supply path 15 connected to an air inlet 3 are provided. The cutoff film 32 and the purge channel 30 that connects the fuel gas inlet 2 and the exhaust gas outlet 27 are provided. During operation, the fuel electrode exhaust gas and the air electrode exhaust gas are subjected to a combustion reaction and then exhausted, and when the operation is stopped, they are purged with the air electrode exhaust gas and then sealed by a blocking film 22. As a result, pressure drop due to residual gas consumption and outside air and water,
It is possible to prevent foreign matter from entering.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, and more particularly to a power supply device using a fuel cell.

[0002]

2. Description of the Related Art A fuel cell of a phosphoric acid type, a molten carbonate type, a solid electrolyte type or the like uses a chemical energy of a supplied gas as a fuel cell.
Since it can be directly converted into electric energy, high power generation efficiency can be obtained. Moreover, these fuel cells are
It is being put into practical use from a large one of 00 kW to a small one of about several hundred W. Among them, particularly small fuel cells are used as power sources for transportation of golf carts, communications, construction and civil engineering work, for example.

By the way, in the conventional power supply device using the above-mentioned small fuel cell, air inlets and reaction gas outlets are provided on a plurality of surfaces of the case in which the fuel cell main body is housed, and when the power source is not used, these are used. Outside air may enter the case through the intake and exhaust ports. As a result, the electrolyte (for example, phosphoric acid) of the fuel cell absorbs moisture in the outside air, so that there is a problem that the electrolyte concentration is lowered and the cell characteristics are deteriorated.

Therefore, as a conventional example for avoiding such a situation, there is one disclosed in Japanese Patent Application Laid-Open No. 5-190196. The configuration will be described below with reference to FIG. 7. The power supply device shown in FIG. 7 includes a fuel cell main body 1 that performs a power generation operation using hydrogen as a fuel, a hydrogen storage device 2 made of a hydrogen storage alloy that supplies hydrogen to the fuel cell main body 1, and the fuel cell main body 1 and the hydrogen storage device 2. An air intake port 5 for taking in air necessary for fuel cell power generation operation is formed on one surface of the case body 3 and comprises a case body 3 for accommodating the storage device 2 and a lid body 4 for covering the case body 3.
And a reaction gas outlet 6 for exhausting the reaction gas generated by the fuel cell power generation operation, and these intake and exhaust ports 5, 6 are closed by the lid 4 when the power source is not used. , When not using the power supply,
Since 6 is sealed by the lid 4, these intake / exhaust ports 5,
6, the outside air and the like enter the case body 3, and the moisture in the outside air prevents the concentration of the electrolyte (for example, phosphoric acid) of the fuel cell from decreasing, so that the deterioration of the cell characteristics can be prevented. It was

[0005]

However, in the power supply device having the above-described structure, since the cover 4 is used to shut off the outside air, the seal is provided rather than the shutoff at each of the intake and exhaust ports 5 and 6. The range increases. If the sealing range is large, minute gaps are likely to occur in the seal portion, and water molecules in the gas are very small and easily pass through even a slight gap, so that water enters and leaves between the case body 3 and the outside air, and There is a problem that the electrolyte concentration is likely to decrease due to the water content.

Further, even when the use of the power source is terminated and the inlet / outlet ports 5 and 6 are closed by the lid 4, the electrochemical reaction in the fuel cell body 1 is continued until the residual gas is exhausted, and the case body is consumed due to the consumption of the residual gas. The pressure inside 3 decreases, and due to this pressure decrease, there is no sealing means at the hydrogen supply port, so hydrogen as fuel continues to be consumed, or the pressure becomes smaller than the outside air, and the outside air or foreign matter is likely to enter due to leakage. There is a problem of becoming. Further, if the pressure in the case body 3 is reduced to a negative pressure when the power source is not used, the pressure difference is large when gas is supplied when starting to use the power source, which causes a problem of being easily broken by impact.

The present invention solves the above-described conventional problems. When the power source is not used, the fuel cell main body is sealed to prevent the invasion of outside air, foreign matter and the like into the fuel cell main body, and the fuel cell after the operation is stopped. The main purpose is to prevent pressure drop due to consumption of residual gas in the body.

[0008]

In the power supply device of the present invention, the combustion is provided with an exhaust gas outlet for introducing and burning both gases discharged from the fuel gas outlet and the air outlet of the fuel cell body to discharge combustion exhaust gas. And a sealing means provided in the air supply passage of the fuel cell main body, and a purge flow passage connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion portion.

According to the present invention, the danger of ignition or explosion due to the exhaust gas discharged from the power supply device can be prevented, and the fuel gas in the fuel electrode is purged by the inert exhaust gas to continue the electrochemical reaction. Therefore, it is possible to prevent pressure drop due to consumption of residual gas in the fuel cell body.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has the following constitution in order to solve the above problems. That is, as the first configuration,
A fuel cell main body for generating power by an electrochemical reaction between a fuel gas and oxygen in the air, and an exhaust gas outlet for introducing and burning both gases discharged from the fuel gas outlet and the air outlet of the fuel cell main body to discharge combustion exhaust gas. And a combustor having an air supply passage communicating with an air inlet of the fuel cell main body, and connecting a fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion portion. And a purge flow path for

As a second structure, a fuel gas discharge passage connecting the fuel gas outlet and the combustion portion, an air discharge passage connecting the air outlet and the combustion portion, and the fuel electrode exhaust gas is forcibly combusted. And a storage battery for driving the pressure-feeding means, the pressure-feeding means having a pressure-feeding means to be introduced into the section and provided in parallel with the fuel gas discharge passage.

As a third structure, an aspirator portion provided in the middle of the air discharge passage, a branch portion provided in the middle of the fuel gas discharge passage connecting the fuel gas outlet and the combustion portion, and the aspirator portion. And a suction passage that connects the branch portion to each other, and a shutoff valve is provided in the middle of the suction passage.

As a fourth structure, an oxygen concentration detecting means is provided in the purge flow path connecting the fuel gas inlet of the fuel cell body and the exhaust gas outlet of the combustion section.

As a fifth structure, a volume section is provided downstream of the exhaust gas outlet of the combustion section.

In a sixth structure, one end is connected to the fuel gas inlet of the fuel cell main body, and the other end is connected to the exhaust gas outlet of the combustion section and has a purge passage having a detachable connecting means, and the connecting means. The purging flow passage is provided with a purging flow passage closing portion that can be attached and detached.

As a seventh structure, a passage switching electromagnetic valve is provided at the exhaust gas outlet of the combustion section to which the purge passage is connected or at the downstream thereof, the purge passage is closed when energized, and when not energized. The exhaust gas outlet is closed.

As an eighth structure, the sealing means is airtight and liquid-tight and comprises a film-shaped or sheet-shaped blocking film for covering the air supply passage.

As a ninth structure, a check valve which is opened as a sealing means is provided in the air supply passage when the pressure on the upstream side of the fuel cell body becomes higher than the pressure in the fuel cell body by a predetermined pressure. It is a thing.

The present invention has the following effects due to the above configuration. That is, it has a combustion part having an exhaust gas outlet that introduces both gases discharged from the fuel gas outlet and the air outlet of the fuel cell body of the first configuration to burn and discharge combustion exhaust gas. Due to the structure provided with the sealing means provided in the supply path and the purge flow path connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion section, the fuel that could not completely react in the fuel electrode during operation Since the fuel component of the polar exhaust gas is burned in the combustion section, it is possible to prevent the risk of ignition or explosion due to the exhaust gas discharged from the power supply device, and when the operation is stopped, the purge gas passage connects the fuel gas inlet and the exhaust gas outlet, By introducing the exhaust gas exhausted from the exhaust gas outlet due to oxygen consumption in the main body and the combustion part into the fuel gas inlet, the fuel gas in the fuel electrode is purged by the inert exhaust gas and the electrochemical reaction Since it becomes impossible to continue, it is possible to prevent the pressure drop due to the residual gas consumed in the fuel cell body. When the air supply passage is closed by the sealing means after the end of purging, the fuel cell main body is surely closed within a small sealed area of the air supply passage when the power supply is not used. It is possible to prevent the entry of foreign matter and the like, and to prevent a decrease in electrolyte concentration and deterioration of battery characteristics due to absorption of moisture in the outside air.

Further, in the second structure, the fuel gas discharge passage connecting the fuel gas outlet and the combustion portion, the air discharge passage connecting the air outlet and the combustion portion, and the fuel gas discharge passage are provided in parallel. With the configuration including the pressure feeding path having the pressure feeding means and the storage battery for driving the pressure feeding means, the fuel gas discharge path connected to the combustion section during the operation of the power supply device is removed when the operation is stopped, and the pressure feeding means is used as the storage battery. It is possible to supply to the combustion part the fuel electrode exhaust gas that consumes the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion part from the air discharge path and is driven by the stored electric power, so the residual oxygen and fuel gas The fuel gas of the fuel electrode can be safely purged without causing sudden heat generation and explosion, and the operation can be stopped easily with a simple structure.The power supply prevents pressure drop due to consumption of residual gas after the operation is stopped. Power outside the device It can be carried out without supply.

Further, in the third structure, an aspirator portion provided in the middle of the air discharge passage, a branch portion provided in the middle of the fuel gas discharge passage connecting the fuel gas outlet and the combustion portion, an aspirator portion and the branch. And a suction valve connecting to the combustion chamber and a shut-off valve provided in the middle of the suction channel.If the fuel gas discharge channel connected to the combustion section during operation of the power supply is removed when operation is stopped, the air discharge channel is removed. By the action of the aspirator part provided in the, the fuel electrode exhaust gas, which consumes the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion part from the air discharge path by combustion, can be sucked into the combustion part from the suction path. Reacts in the fuel electrode, and the fuel gas in the fuel electrode can be safely purged without causing sudden heat generation or explosion, and the operability at the time of operation stop can be improved with a simple configuration, and the residual gas consumption after operation stop Pressure drop It is possible to perform the stop without consuming the power generation output.

According to the fourth structure, the oxygen concentration detecting means is provided in the purge passage connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion section. Since it is possible to monitor the residual oxygen concentration in the exhaust gas of the combustion part that is introduced into the fuel cell, even if the residual oxygen concentration becomes large, the residual oxygen and the fuel gas react in the fuel electrode and sudden heat generation or explosion occurs. Since the introduction of the exhaust gas can be stopped before it is generated, it is possible to safely perform the purge for preventing the pressure drop due to the residual gas consumption after the operation is stopped.

Further, according to the fifth structure, in which the volume part is provided downstream of the exhaust gas outlet of the combustion part, the combustion part exhausted after oxygen is sufficiently consumed in the fuel cell main body and the combustion part during the operation of the power supply device. Since the exhaust gas can be stored in the volume, purging can be performed safely and reliably with a sufficient amount of the inert gas when the operation is stopped.

Further, in the sixth structure, one end is connected to the fuel gas inlet of the fuel cell main body, and the other end has a purge passage having a detachable connecting means at the exhaust gas outlet of the combustion section, and a purge flow by the connecting means. Due to the configuration with a purge flow path closing part with removable passage, the purge flow path that was closed by being connected to the purge flow path closing part during operation of the power supply was removed from the flow path closing part when operation was stopped, and combustion was performed. By connecting the purge flow passage so that it can be purged by attaching it to the exhaust gas outlet of the section, the flow passage can be switched at the time of operation and at the time of operation stop for sealing and pressure drop prevention with a simple structure with low cost and good operability. It can be carried out.

In the seventh construction, a passage switching solenoid valve is provided at the exhaust gas outlet of the combustion section to which the purge passage is connected or at the downstream thereof, and the purge passage is closed when energized and the exhaust gas is de-energized. With the configuration that the exhaust port is closed, the purge flow path is closed by energizing the flow path switching solenoid valve from the power supply device while the power supply device is operating, and when the operation is stopped, the power supply to the flow path switching solenoid valve is also stopped and the exhaust gas exhaust port Is closed and the purge flow path is in communication, so the discharge of combustion exhaust gas from the exhaust gas outlet is stopped, and the fuel gas inlet and the exhaust gas outlet of the combustion section are automatically connected by the purge flow path, so it is possible to operate and stop operation. It is possible to automatically switch the flow passages to prevent airtightness and pressure drop with a small number of parts without user operation.

Further, the sealing means of the eighth construction is airtight and liquid-tight, and is constituted by a film-shaped or sheet-shaped blocking film that covers the air supply passage, so that the components of the sealing means are blocked. Since it is possible to use only the membrane, the sealing method is simple, the cost is low, and the weight of the power source can be reduced.

In the ninth construction, the seal means is provided with a check valve which opens in the air supply passage only under a predetermined condition, so that only when the air is supplied and the air flows from the upstream side to the downstream side, the pressure difference is reversed. When the stop valve opens and the gas supply is stopped when the power supply is finished, the pressure difference disappears and the check valve closes.Therefore, the simple structure does not require opening and closing of the sealing means when the power supply is used and when it is not used. You can drive and stop.

Embodiments of the present invention will be described below with reference to the drawings. 1 is a plan sectional view of a power supply device according to a first embodiment of the present invention, and FIG. 2 is a front view thereof. In FIG. 1 and FIG. 2, a fuel cell main body 6 in which four supply / discharge ports of a fuel gas inlet 2, an air inlet 3, a fuel gas outlet 4 and an air outlet 5 are provided inside a power supply device main body 1 and a reformer. 7 and fan 8 are stored. Raw fuel supply port 9 of power supply unit 1
And the reformer 7 are connected by a conduit 10, the reformer 7 and the fuel cell body 6 are connected to the fuel gas inlet 2, and a fuel gas supply path 13 having a valve 11 and an inlet branch 12 downstream thereof is provided in the middle thereof. It is connected. The air supply port 14 provided in the power supply device body 1 is connected to the air inlet 3 of the fuel cell body 6 by the air supply passage 15, and the fan 8 and the fuel cell body 6 are connected.
Is connected to the air supply port 14 by a fan connection conduit 16 which is detachably formed.

Connected to the fuel gas outlet 4, the outlet branch 1
The fuel gas discharge passage 18 including 7 is detachably connected to the fuel exhaust gas introduction port 19 provided in the power supply device main body 1 around the outside of the power supply device main body 1 by the connecting means 20 and connected to the combustion part 21. Has become. The power supply device main body 1 has the same shape as the fuel exhaust gas inlet 19, and the connecting means 20 of the fuel gas exhaust passage 18 can be connected to the fuel gas exhaust passage 1
A fuel gas discharge passage closing portion 22 capable of closing 8 is provided. In addition, the pressure feeding means 23 branched from the outlet branching portion 17 of the fuel gas discharging passage 18 and provided in parallel with the fuel gas discharging passage 18 joins the fuel gas discharging passage 18 and connects to the combustion portion 21 on the way. 24 is provided, and the pressure feeding means 24 is electrically connected to the storage battery 25 in the power supply device body 1.

The other end of the air discharge path 26 connected to the air outlet 5 is connected to the combustion section 21, and the exhaust gas outlet 27 provided in the combustion section 21 is provided in the power supply unit main body 1 via the volume section 28. It communicates with the exhaust gas discharge port 29. On the other hand, the purge flow passage 30 connected to the inlet branch portion 12 of the fuel gas supply passage 13 can be attached to and detached from the exhaust gas outlet 29 provided in the power supply device main body 1 around the outside of the power supply device main body 1 by the connecting means 20. Is connected to the exhaust gas outlet 27 of the combustion section 21. Further, the power supply device main body 1 is provided with a purge passage closing part 31 which has the same shape as the exhaust gas outlet 29 and which can connect the connecting means 20 of the purge passage 30 and can close the purge passage 30.

With the above structure, when the power source is used, the fan connection conduit 16 is connected to the air supply port 14, the fuel gas discharge passage 18 is connected to the fuel exhaust gas introduction port 19, and the purge flow passage 30 is connected to the purge flow passage closing portion 31. Connected, Figure 3 (a)
The circuit is as shown in the block diagram of. Then, the hydrocarbon-based or alcohol-based raw fuel supplied from the raw fuel supply port 9 by a cylinder or the like (not shown) passes through the conduit 10 and serves as fuel gas for power generation in the fuel cell by the reformer 7. Reformed into hydrogen-rich gas. Purge channel 3
Since 0 is connected to and closed by the purge flow path closing part 31, the reformed fuel gas passes through the open valve 11,
It is supplied to the fuel cell main body 6 from the fuel gas inlet 2 through the inlet branch portion 12 without passing through the purge flow passage 30 side. on the other hand,
The air that is the oxidant gas is supplied to the air supply port 1 by the fan 8.
4 is supplied to the fuel cell main body 6 from the air inlet 3 via the air supply passage 15 through the fan connection conduit 16 connected to the fuel cell main body 6, and causes an electrochemical reaction with the fuel gas to generate electricity.

The fuel electrode exhaust gas that has exited the fuel cell main body 6 is introduced from the fuel gas outlet 4 to the combustion section 21 through the fuel gas discharge passage 18 or the pressure feed passage 23, and the cathode exhaust gas is sent to the air outlet 5
Is introduced into the combustion section 21 through the air discharge path 26, the two exhaust gases are subjected to combustion reaction in the combustion section 21, and the combustion exhaust gas is discharged from the exhaust gas outlet 27. The combustion exhaust gas discharged from the exhaust gas outlet 27 is stored in the volume part 28, and when the volume part 28 becomes full and the combustion exhaust gas exceeds the capacity of the volume part 28, the combustion exhaust gas is discharged to the outside air from the exhaust gas discharge port 29. As a result, the fuel component of the fuel electrode exhaust gas that has not completely reacted in the fuel electrode of the fuel cell main body 6 during operation is burned in the combustion section 21, so that there is a risk of ignition or explosion due to the exhaust gas discharged from the power supply device main body 1. Can be prevented.

After use of the power source, as shown in FIGS. 1 and 2, the supply of raw fuel is stopped, the valve 11 of the fuel gas supply passage 13 is closed, and the fuel gas discharge passage 18 is introduced into the fuel exhaust gas. The purge channel 30 is removed from the port 19, and the purge channel 30 is removed from the purge channel closing part 31 and connected to the exhaust gas outlet 29 to form a circuit as shown in the block diagram of FIG. 3B.

Since the fan 8 continues to be driven, the cathode exhaust gas from the air outlet 5 of the fuel cell body 6 is introduced into the combustion section 21, while the anode exhaust gas from the fuel gas outlet 4 is stored in the storage battery. From the outlet branch portion 17 to the pressure feeding path 2 by the action of the pressure feeding means 24 driven by the electric power stored in 25.
3, the fuel exhaust gas inlet 19 is connected to the fuel gas discharge passage 18
Since the structure is shielded by removing the
Introduced in 1. At this time, the fuel electrode exhaust gas that consumes only the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion unit 21 from the air discharge passage 26 in the combustion reaction is sent by the pumping unit 24 to the combustion unit 2
Oxygen electrode exhaust gas containing residual oxygen that could not be completely consumed in the fuel cell main body 6 in the combustion section 21,
Oxygen is consumed in the combustion exhaust gas due to the combustion reaction with the anode exhaust gas. By introducing this combustion exhaust gas into the fuel gas inlet 2 through the purge flow path 30, the residual oxygen reacts with the fuel gas in the fuel electrode, and the fuel gas in the fuel electrode is inactive without sudden heat generation or explosion. It is safely purged by various combustion exhaust gases, making it impossible to continue the electrochemical reaction. At the time of this purging, for example, operation control is performed so as to stop the combustion reaction in the combustion section 21 together with the supply of the raw fuel, or even if the combustion reaction is stopped for some reason, the fuel cell is operating while the power supply device is operating. Since the exhaust gas of the combustion part, which has been exhausted due to sufficient oxygen consumption in the main body 6 and the combustion part 21, is stored in the volume part 28, it can be purged by a sufficient amount of the inactive combustion exhaust gas when the operation is stopped. Exhaust gas in which oxygen is consumed disappears, and exhaust gas containing oxygen and the fuel gas are prevented from reacting with each other to cause rapid heat generation and explosion, so that purging can be performed safely and reliably.

After the purging is completed, the fan 8 is stopped, the fan connection conduit 16 connected to the air supply port 14 is removed, the fuel gas discharge passage 18 is connected to the fuel gas discharge passage closing portion 22, and an airtight seal is provided. .Liquid-tight barrier film 3
2 is attached to the air supply port 14 so as to cover the air supply passage 15. Since one surface of the blocking film 32 is coated with an adhesive material (not shown) for sticking to the supply port, the blocking film 32 can be sealed easily and at low cost, and the weight of the power supply can be reduced. . Further, the fuel gas discharge passage 18 and the purge flow passage 30 which are output from the power supply device main body 1 are respectively connected to the fuel gas discharge passage closing portion 2 from the fuel exhaust gas introduction port 19.
2 and from the purge flow path closing part 31 to the exhaust gas discharge port 2
9 is reconnected by using the connecting means 20. Therefore, it is possible to easily perform the flow passage switching operation related to sealing and purging at the time of operation and at the time of operation stop on the same surface, and it is easy and costly to prevent sealing and pressure drop. Can be realized without.

Therefore, when the power source is not used, the shut-off film 32 attached to the air supply port 14 and the fuel gas discharge passage closing portion 2
The fuel gas discharge passage 18 and the purge flow passage 30 which are connected to the fuel cell 2 and the purge flow passage 30 securely seal the fuel cell main body 6 in a small sealed area of the air supply passage 15, so that the outside air into the fuel cell main body 6 is prevented. It is also possible to prevent intrusion of water, foreign matter, and the like, to prevent a decrease in electrolyte concentration and deterioration of battery characteristics due to absorption of water in the outside air, and to improve reliability in restarting after long-term storage. Further, by purging with an inert cathode exhaust gas, it is possible to prevent a pressure drop due to consumption of residual gas in the sealed fuel cell main body 6, thereby improving the reliability of the sealing means and supplying a power source starting gas. The impact of can be prevented. Further, since the residual oxygen is purged with the combustion exhaust gas that has sufficiently consumed in the combustion section 21, the residual oxygen and the fuel gas react with each other in the fuel electrode, and the fuel gas in the fuel electrode can be safely purged without causing sudden heat generation and explosion. With a simple configuration, the operation stop operation can be simplified, and the pressure drop due to the residual gas consumption after the operation stop can be prevented without supplying power outside the power supply device.

Here, the fuel gas discharge passage closing portion 22 is provided in the main body 1 of the power supply device, and the fuel gas discharge passage 18 is connected and sealed to the fuel gas discharge passage closing portion 22 when the power source is not used. It is obvious that the fuel gas discharge passage 18 can be similarly sealed by reconnecting the fuel gas discharge passage 18 to the fuel exhaust gas introduction port 19 without providing the passage closing portion 22.

FIG. 4 is an enlarged cross-sectional view of a main part of a power supply device according to a second embodiment of the present invention, in which the same reference numerals as those in FIGS. 1 and 2 represent corresponding components, and detailed description thereof will be omitted. . In the figure, reference numeral 33 is a check valve provided in the air supply passage 15, and a valve body 35 is arranged on the air inlet 3 side (downstream side) of a valve seat 34 formed in the air supply passage 15 A spring 37 supported by a spring support portion 36 is provided further downstream of 35, and the valve element 35 is opened only when a predetermined opening pressure is applied before and after the check valve 33.

In the above structure, since air is supplied and a supply pressure is applied when the power supply is used, the check valve 33 is applied with a pressure equal to or higher than a predetermined opening pressure from the upstream air supply port 14 side, and the check valve 33 is supplied. 33 is opened so that air can flow from the air inlet 3 into the fuel cell body 6. When the use of the power source is completed and the purging is completed, the fan 8 is stopped to stop the air supply and the fan connection conduit 16 connected to the air supply port 14 is removed, so that the pressure difference before and after the check valve 33 disappears. Since the check valve is closed, when the fuel gas discharge passage 18 is closed as described above, the inside of the fuel cell body 6 becomes a sealed state, and it is possible to prevent the invasion of outside air, moisture, foreign matters, etc. It is possible to start and stop without using the opening and closing operation of the sealing means when using and when not using the power supply.

5 (a) and 5 (b) are block diagrams of a power supply device according to a third embodiment of the present invention.
Shows a circuit at the time of power generation operation, FIG. 5 (b) shows a circuit at the time of purge operation, and those having the same reference numerals as those in FIGS. 1, 2, 3 (a) and 3 (b) are corresponding components. Yes, detailed description is omitted. In the figure, reference numeral 38 denotes a combustion exhaust gas flow passage that connects the exhaust gas outlet 27 of the combustion unit 21 to the volume 28 and the exhaust gas outlet 29, and the fan control unit 39 includes the fan 8 and
The storage battery 25 and the hydrogen concentration detecting means 40 provided in the combustion exhaust gas passage 38 are electrically connected to each other.
Then, the hydrogen concentration signal detected by the hydrogen concentration detecting means 39 during the operation of the power supply device is sent to the fan control unit 38, and when the residual hydrogen content is detected in the combustion exhaust gas, the electric power from the storage battery 25 is controlled. The amount of air supplied by the fan 8 is adjusted so that the combustor 21 consumes a sufficient amount of hydrogen to prevent the risk of ignition or explosion due to the exhaust gas discharged from the power supply device body 1. . A flow path switching solenoid valve 41 for switching the combustion exhaust gas passing through the exhaust gas flow path 38 to the exhaust gas discharge port 29 side or the purge flow path 30 side is provided in the middle of the combustion exhaust gas flow path 38 downstream of the exhaust gas outlet 27. When the power is on, the purge channel 30 is closed to open the exhaust gas outlet 29 side, and when the power is off, the exhaust gas outlet 29 side is closed to open the purge channel 30. Further, the pressure-feeding means control unit 42 is electrically connected to the pressure-feeding means 24, the storage battery 25, the oxygen concentration detection means 43 provided in the purge passage 30, and the display unit 44.

In the above-mentioned structure, FIG.
As shown in (a), due to the electrochemical reaction associated with power generation,
The flue gas discharged from the flue gas outlet 27 after oxygen is consumed in the fuel cell main body 6 and the combustion section 21 is stored in the volume section 28 downstream of the flue gas outlet 27, and when the volume section 28 becomes full, excess combustion gas flow is generated. While energizing from the passage 38, it passes through the passage switching solenoid valve 41 open to the exhaust gas outlet 29 side,
It is discharged from the exhaust gas discharge port 29. After the power source is used, as shown in FIG. 5B, when the raw fuel supply is stopped and the raw fuel supply port 9 is closed to stop the operation, the passage switching electromagnetic valve 41 is deenergized. As a result, the flow path switching electromagnetic valve 41 opens to the purge flow path 30 side, the purge flow path 30 communicates from the exhaust gas outlet 27 to the fuel gas inlet 2, and the purge starts.
In this way, along with the operation of the power supply device and the operation of stopping the power supply device, the closing of the purge flow path 30 during the operation of the power supply device and the communication of the purge flow path 30 during the purge operation are automatically performed by the flow path switching electromagnetic valve 41. Therefore, the user can operate the connection of the purge passage 30 during the operation and the purge operation, the sealing of the fuel gas inlet 2 and the switching of the purge passage to prevent the pressure drop with a small number of parts. It can be done automatically without. The oxygen concentration signal detected by the oxygen concentration detection means 43 during the purge operation is the pressure feeding means control unit 4
2 and the residual oxygen is detected in the combustion exhaust gas, the electric power from the storage battery 25 is controlled to adjust the flow rate of the fuel electrode exhaust gas by the pressure feeding means 24, so that the combustion portion 21 sufficiently consumes the oxygen content. It is like this. Further, the oxygen concentration signal from the oxygen concentration detecting means 43 is compared with the concentration stored in the pressure-feeding means control unit 42 that causes rapid heat generation or explosion,
If the concentration is dangerous for some reason, the display unit 44 displays a dangerous display. As a result, it is possible to monitor the residual oxygen concentration in the combustion exhaust gas introduced to the fuel electrode side through the purge flow path 30, so that even if the residual oxygen concentration becomes high, the residual oxygen and the fuel gas will not Since the passage switching electromagnetic valve 41 can be manually switched to stop the introduction (purge) of the combustion exhaust gas before the reaction occurs in the fuel electrode of the cell body 6 and abrupt heat generation or explosion occurs, the operation after the operation is stopped. It is possible to safely perform the purge for preventing the pressure drop due to the residual gas consumption.

In the description here, when the oxygen concentration signal is a dangerous concentration, the flow passage switching valve 41 is manually switched by looking at the danger display on the display unit 44. However, the output signal of the oxygen concentration detection means 43 is used. A configuration may be provided in which the purge is automatically switched to the purge stop side. Further, although the flow passage switching valve 41 is provided in the middle of the combustion exhaust gas flow passage 38 which is downstream of the volume portion 28, when the volume portion 28 is not provided, the exhaust gas outlet 27 is provided.
The flow path switching valve 41 may be provided in the.

6 (a) and 6 (b) are block diagrams of a power supply device according to a fourth embodiment of the present invention.
6 shows a circuit during power generation operation, and FIG. 6 (b) shows a circuit during purge operation. FIGS. 1, 2, 3 (a), 3 (b), 5
The same reference numerals as those in (a) and FIG. 5 (b) are corresponding components, and detailed description thereof will be omitted. In the figure, an aspirator section 45 is provided in the vicinity of the combustion section 21 in the middle of the air discharge path 26, and an outlet branch section 1 provided in the middle of the fuel gas discharge path 18 connecting the fuel gas outlet 4 and the combustion section 21.
7 and the aspirator portion 45, a shutoff valve 46 is provided on the way.
Is connected to the suction path 47.

In the above structure, the shutoff valve 46 is closed during the operation of the power source device, and the fuel electrode exhaust gas that has exited the fuel gas outlet 4 of the fuel cell body 6 is passed through the fuel gas exhaust passage 18 that is connected to the fuel exhaust gas inlet 19. The circuit as shown in the block diagram of FIG. Then, when the fuel gas discharge passage 18 that is connected to the fuel exhaust gas introduction port 19 and communicates with the combustion part 21 during the operation of the power supply device is removed from the fuel exhaust gas introduction port 19 when the operation is stopped and the shutoff valve 46 is opened, Due to the suction action of the aspirator portion 45 provided in the exhaust passage 26, the fuel electrode exhaust gas that consumes only the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion portion 21 from the air exhaust passage 26 by combustion from the suction passage 26 to the combustion portion 21. Since it can be sucked, residual oxygen reacts with the fuel gas in the fuel electrode, and the fuel gas in the fuel electrode can be safely purged without sudden heat generation or explosion, and the operability of stopping at the time of operation stop is improved with a simple configuration. It is possible to prevent pressure drop due to residual gas consumption after operation stop without consuming power generation output.

In the embodiment of the present invention, the fuel cell body 6
Although the shutoff membrane 32 or the check valve 33 as the sealing means is provided in the air supply path 15 connected to the air inlet 3, the same effect can be obtained by directly providing the sealing means in the air inlet 3.

[0046]

As described above, the power supply of the present invention has the following effects.

That is, the fuel cell has a combustion part having an exhaust gas outlet for introducing and combusting both gases discharged from the fuel gas outlet and the air outlet of the fuel cell main body of the first structure, and discharging the combustion exhaust gas. Since a sealing means provided in the air supply path of the main body and a purge flow path connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion section are provided, reaction in the fuel electrode occurs during operation. Since the fuel component of the fuel electrode exhaust gas that could not be burned is burned in the combustion section, it is possible to prevent the risk of ignition and explosion due to the exhaust gas discharged from the power supply device,
When the operation is stopped, the fuel gas inlet and the exhaust gas outlet are connected by the purge flow path, and the exhaust gas exhausted from the exhaust gas outlet due to the consumption of oxygen in the fuel cell main body and the combustion part is introduced into the fuel gas inlet. Since the fuel gas in the fuel cell is purged by the inactive exhaust gas and it becomes impossible to continue the electrochemical reaction, it is possible to prevent the pressure drop due to the consumption of residual gas in the fuel cell body after the sealing, and thus the sealing The reliability of the means can be improved, and the shock at the time of supplying the power supply starting gas can be prevented. When the air supply passage is closed by the sealing means after the end of purging, the fuel cell main body is surely closed within a small sealed area of the air supply passage when the power supply is not used. It is possible to prevent the entry of foreign matter and the like, to prevent the decrease of the electrolyte concentration and the deterioration of the battery characteristics due to the absorption of moisture in the outside air, and to improve the reliability at the time of restarting after long-term storage.

Further, in the second structure, the fuel gas discharge passage connecting the fuel gas outlet and the combustion portion, the air discharge passage connecting the air outlet and the combustion portion, and the fuel gas discharge passage are provided in parallel. Since the configuration is provided with the pressure feeding path having the pressure feeding means and the storage battery for driving the pressure feeding means, the fuel gas discharge path connected to the combustion section during operation of the power supply device is removed when the operation is stopped, and the pressure feeding means is provided. It can be driven by the electric power stored in the storage battery, and the fuel electrode exhaust gas, which consumes the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion part from the air discharge path by combustion, can be supplied to the combustion part. It reacts in the electrode and can safely purge the fuel gas of the fuel electrode without causing sudden heat generation and explosion, and realizes the simplification of the operation stop operation with a simple structure and prevents the pressure drop due to the consumption of residual gas after the operation stop. Outside the power supply It is possible to perform power without supplying.

Further, in the third structure, an aspirator section provided in the middle of the air discharge path, a branch section provided in the middle of the fuel gas discharge path connecting the fuel gas outlet and the combustion section, an aspirator section and the branch. It has a suction passage connecting to the engine and a shut-off valve provided in the middle of the suction passage.Therefore, if the fuel gas discharge passage connected to the combustion unit during operation of the power supply is removed when operation is stopped, Due to the suction action of the aspirator part provided in the discharge path, the fuel electrode exhaust gas that consumes the residual oxygen content of the oxygen electrode exhaust gas that enters the combustion part from the air discharge path by combustion can be sucked into the combustion part from the suction path. The fuel gas reacts in the fuel electrode, and the fuel gas in the fuel electrode can be safely purged without causing sudden heat generation and explosion. For gas consumption That pressure drop prevented can be performed without consuming power output, thereby improving the operation efficiency.

In the fourth structure, the oxygen concentration detecting means is provided in the purge flow path connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion section. Since it is possible to monitor the residual oxygen concentration in the exhaust gas of the combustion section introduced to the fuel electrode, even if the residual oxygen concentration becomes high, the residual oxygen and the fuel gas react in the fuel electrode and sudden heat generation or Since the introduction of the exhaust gas can be stopped before the explosion occurs, it is possible to safely perform the purge for preventing the pressure drop due to the residual gas consumption after the operation is stopped.

Further, in the fifth structure, since the volume part is provided downstream of the exhaust gas outlet of the combustion part, the combustion exhausted after oxygen is sufficiently consumed in the fuel cell main body and the combustion part during the operation of the power supply device. Since the exhaust gas of a certain portion can be stored in the volume portion, it is possible to safely and reliably perform the purging with a sufficient amount of the inactive combustion exhaust gas when the operation is stopped.

In the sixth structure, one end is connected to the fuel gas inlet of the fuel cell main body, and the other end has a purge flow path having a detachable connecting means at the exhaust gas outlet of the combustion section, and a purge flow by the connecting means. Since the flow path is configured to have a removable purge flow path closing part, the purge flow path that was closed by being connected to the purge flow path closing part while the power supply was operating is removed from the flow path closing part when operation is stopped. By connecting the purge flow path so that it can be purged by attaching it to the exhaust gas outlet of the combustion part, the flow path switching for operating and shutting down and preventing pressure drop can be operated with low cost and simple structure. You can do it with good sexuality.

In the seventh structure, a passage switching electromagnetic valve is provided at the exhaust gas outlet of the combustion section to which the purge passage is connected or at the downstream thereof, the purge passage is closed when energized, and the exhaust gas is shut off when not energized. Since the outlet is closed, the purge flow path is closed by energizing the flow path switching solenoid valve from the power supply while the power supply is operating, and the flow path switching solenoid valve is also de-energized when operation is stopped. Since the exhaust port is closed and the purge flow path is in communication, the discharge of combustion exhaust gas from the exhaust gas exhaust port is stopped, and the fuel gas inlet and the exhaust gas outlet of the combustion section are automatically connected by the purge flow path. It is possible to automatically switch the flow passages to prevent airtightness and pressure drop when the operation is stopped with a small number of parts and without user operation.

Further, the sealing means of the eighth construction is airtight and liquid-tight, and is constituted by a film-shaped or sheet-shaped blocking film for covering the air supply passage, so that the constituent parts of the sealing means are Since only the blocking film can be used, the sealing method is simple and inexpensive, and the weight of the power source can be reduced.

Further, in the ninth construction, since the check valve that opens only when a predetermined condition is provided is provided in the air supply passage as the sealing means, the pressure difference is generated only when the air is supplied and flows from the upstream to the downstream. The check valve will open and the pressure difference will disappear when the gas supply is stopped when the power supply is finished.The check valve will close, so the opening and closing of the sealing means is required when the power supply is used and when the power supply is not used. You can start and stop without doing this.

[Brief description of drawings]

FIG. 1 is a plan sectional view of a power supply device according to a first embodiment of the present invention.

FIG. 2 is a front view of the device.

FIG. 3A is a block diagram of the apparatus during a power generation operation, and FIG. 3B is a block diagram of the apparatus during a purge operation.

FIG. 4 is an enlarged cross-sectional view of a main part of a power supply device according to a second embodiment of the present invention.

FIG. 5 (a) is a block diagram of a power supply device according to a third embodiment of the present invention during a power generation operation, and (b) is a block diagram of the same device during a purge operation.

FIG. 6A is a block diagram of a power supply device according to a fourth embodiment of the present invention during a power generation operation, and FIG. 6B is a block diagram of the same device device during a purge operation.

FIG. 7 is a perspective view of a conventional power supply device.

[Explanation of symbols]

 2 Fuel Gas Inlet 3 Air Inlet 4 Fuel Gas Outlet 5 Air Outlet 6 Fuel Cell Main Body 15 Air Supply Path 21 Combustion Part 27 Exhaust Gas Outlet 30 Purge Flow Path 32 Blocking Membrane

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H01M 8/06 H01M 8/06 B

Claims (9)

[Claims] 1. A fuel cell body for generating power by an electrochemical reaction between a fuel gas and oxygen in the air, and a combustion exhaust gas produced by introducing and burning both gases discharged from a fuel gas outlet and an air outlet of the fuel cell body. A combustion unit having an exhaust gas outlet for discharging the air, a sealing means provided in an air supply path communicating with an air inlet of the fuel cell body, a fuel gas inlet of the fuel cell body, and the exhaust gas outlet of the combustion unit. And a purge flow path for connecting the power supply device. 2. A fuel gas discharge path connecting the fuel gas outlet and the combustion section, an air discharge path connecting the air outlet and the combustion section, and a pressure feeding means for forcibly introducing the fuel electrode exhaust gas into the combustion section. 2. The power supply device according to claim 1, further comprising: a pressure feeding path that is provided in parallel with the fuel gas discharge path, and a storage battery that drives the pressure feeding means. 3. An aspirator section provided in the middle of an air discharge path, a branch section provided in the middle of a fuel gas discharge path connecting a fuel gas outlet and the combustion section, the aspirator section and the branch section. The power supply device according to claim 1, further comprising a suction path to be connected, wherein a shutoff valve is provided in the middle of the suction path. 4. The power supply device according to claim 1, 2 or 3, wherein an oxygen concentration detecting means is provided in a purge flow path connecting the fuel gas inlet of the fuel cell main body and the exhaust gas outlet of the combustion section. 5. The power supply device according to claim 1, further comprising a volume portion downstream of the exhaust gas outlet of the combustion portion of the fuel cell main body. 6. A purge passage having one end connected to a fuel gas inlet of a fuel cell main body and a detachable connecting means at an exhaust gas outlet of a combustion section at the other end, and the purge passage being attached and detached by the connecting means. A purge flow passage closing part capable of being provided.
The power supply device according to claim 1. 7. A flow passage switching electromagnetic valve is provided at an exhaust gas outlet of a combustion section to which a purge flow passage is connected or at a downstream thereof, and the purge flow passage is closed when energized and the exhaust gas discharge port is closed when not energized. The power supply device according to claim 1. 8. The power supply device according to claim 1, wherein the sealing means is air-tight and liquid-tight and comprises a film-shaped or sheet-shaped blocking film that covers the air supply passage. 9. A check valve that is opened as a sealing means in the air supply passage when the pressure on the upstream side of the fuel cell body becomes higher than the pressure in the fuel cell body by a predetermined pressure.
The power supply device according to claim 1.